Log barking machine



Oct. 21, 1941. E. v. PRENTIC 2,259,584

LOG BARKING MACHINE Filed Dec. 28, 1937 l lzzvenar.- r V.P tlce Edwa d ren tornIey'.

Patented Oct. 21, 1941 UNITED PATENT OFFICEl Loa` Banning MACHINE EdwardY. Prentice, Portland, Oreg. emitan@ Deeembr 2s, 193i, serial No.. 182,142 e'claims, (ci. 1,4;4-208) My invention relates to log barking machines of. the. general' type. Whereina power driven toolis` employed. to remove. the bark from successive areas presented by rotation `of the logincombination with longitudinal movement thereof in progressive process.

The principal. object of `my .invention is the provision of. means for barking logs While afloat in the storage pond.

. A second object is the provision. of extreme durability of such a. machine byarrangement of the involved momenta and stresses. so. as t require engaging elements. of minimum. dimensions. and Weights affording opportunity to ernploy relatively greatfactors of safety. Other objects and advantages of my invention will be: apparent in the following discourse wherein the significance ofthe reference nu` merals in the accompanying drawing, details of construction and manner of use of atypical machine embodying my invention, andthe particular advantages thereof are explained.

Figure 1 represents avi-ew of the top of the machine and a fragment of a. log in` process therethrough. i.

Figure. 21 represents a. View ofthe end; of the machine and. log shown in Fig-ure 1.

Figure 3 represents a view. of the side of one of the elements of L the machine partially in elevation .and partially in` section; together with fragmentary sections of the supporting structure therefor taken on the line 3. of Figure 1. Figure Lirepresents a section of the cutter-,head and associated parts together With 4a fragmentary section of the log taken on the line` 4.?- of Figure 3. A float comprising the logs li, 2, 3', 4,; and 5, the stringers 6 and l, and the planking as 8, 9', and I0, secured together, accommodate two log. handling units indicated generally by the.` lettersv A and B of identical form, a barking element indicated generally by the letter C,fand con. rtrols thereforindicated generally'by the lettersv D and E.

The log-handling units A and B each comprise an endless` chai-n Il guided by two sheaves l2 "and lf3 and driven by a chainrnulleyld which in turn is actuated in rotation by; a motor I5 through. appI Opriate4 gea-ring; contained in the case le., The case HV is mounted upon a, carriage Ily slidable on the rails IB and I9 loyropera-` tion of a'pneumatic cylinder. 20.V connected thereto by the piston-rod 2.I. 1 A

The barking element comprises a rotary cutter-head 22. made up` o'f centrally mounted knives as 23 in` Figure 3 the cutting edges, ofwhich are disposed to. form an approximately helical Iigure, carried uponl the, shaft 24 journaled in. the beamsiz.. azidz. and. driven. by the meter 21 i. through. appropriate pulleys .2li/Land; 2Q and belts 3,0; and-34, f

The .beams 2.5..;.anlA 26; are rigidly lllied; 3.1151; are mounted. pivctally. at. the. approximate; balance thereof. upon .the horizqntal; shaft 3:2; i111 tegral.; with the member i3. in. turn menate@ pivotally' at; 3.4 and 35.,in the .Standards 3Q and 3.1; integrar witntne carriage 3.8\ s ldazble upenithe rails 39..- and 411.- byv, operation.. Qff the motorL 44|, drivingv the Screw. 4.2l threaded, into the; @are riage.3.8;. i

The position of the. cutter-head 2,2 in, vertical adjustment is..contrelle@v by the hand; lever.: 44. pivot-ally mounted upon. a; stud 4.5 .integral with the member; and formld With a eran arm iiconnectedz to the beam 24; bythe 1111..; 415 pivotanyljoming the same.- Two; screws 4,8 and: 491. servev ta Control and; SeCUIQthe edilltmn. of theA cutter-head inlatelil; inclination'to perf. mit of adjustment of the axis of the cutter-head.,r at inclinations Ifrorn- .the horZQIitell. Sll'tsd. i'10 particular .wor-k; i l' f 1 The precise-Vertical; .adjillimmig Qz the @mieli-1 head; however, to accurately sage the-.depth te whichthe cutter-head. penetrates, is effectedby means otixthei'lyvo.` gage-leyers 5.11. and .5l Which are pivotally mounted .upenthe. spindle 52; .and formedwith arcuate; portions; of radii approximately equal to the radius of' the paths of; the Cutting edges of: the cutter-head 2,2; aS.: illustrated in Figure .3.. atsi. Itis to. b e observed-- that easing. is; independent. of; the relative eleratens of the. los. in Vprocesa and .the iioat. carrying .the mag-rime. in lInsure athis .eshrl nar-.- ticula'rly illustratedwhere .the age-lever .5uis, shownbearing upon .the .s urieuie;A 54 tormedw by the cutterliead :and the. gageelever 51;; is shown bearingY .upon 'the bark.y surface 5.5 .ahead ef.- the, cut.

Y Thel electric motors. for the cutter-head and those. for the .logenandling units areaeentrolled boni as todirectionand sneed by apnrepriete apnaratusirenresentedat D..

Controls. yorftlie pneumatic cylinders efieeted: by the valves. t?- and 5l which. are sunrliedwi-th compressed from. a: pire` 5,8 and. are 'se designedfasA toprovide for the admission ef. come pressed airta either 'end .of' the cylinc lersy and the "release ov air from theV )opposite ends. at controlled rates.. l `.'Iliev essence of the invention resides inv the stresses involved in any rapid processing through`A any machine capable of withstanding the shocks and strains of such prodigious magnitude.-

as are necessarily involved.

Thus the aim in the present vendeavorV is to` provide means for barkingthe log without removing it from its place of storage in the mill pond. This is accomplished by maneuvering the log t6 the machine `or the machine to the login' a common means of support, namely, the water-.5in which both machineand logs float.

The natural properties ofY avlog besides its enormous size and weightinclude.characteristics of form which must be considered. The log may not be circular in cross sectionand almost never approaches-the circular form. It may not be smooth or straight'or havea uniform section or uniform -dimensions thereof. `It may float higher on'one side than another yor it may suddenly turn turtledue to a gradualchange in the relative value ofthe metacentricheight of the displacement of either center of buoyancy or center of gravity. The bark will vary in thickness. All of these vcharacteristics in simple or complex combinations are factors to be dealt with.Y

`No vattempt -is maderto lift the log from the water o'r `even partially do so. Instead, the log is embraced by a wrap of the chain 59 in the form-of i an helix as shown and `the carriage 60 is retracted byoperation of the pneumatic cylinderfGl-t'o draw the chain 59 snugly aboutthe 10g v :l

@The motor- 52 is started and the log .begins to revolve in a counter-clockwise direction as .viewed in Figure 2, and at the same time is impelled forward toward the cutter-head byrvirtue of the gradual movement ofi each of the chain links f romvth'e position where they initially lcontact the log to lthepoint where -they'pay'oi to follow through lthe sheave 63 -in the course of the helical movement thereof.

As the log approaches the cutter-head 22, the

latter is raised by means` of therhand lever 44.

The gage-lever 5| is depressed andthe pressure onlever 44 islessened untilthe cutter-head 'assembly is supported bythe vgage-lever r5| .upon the bark of the log. 'I'.he'gage-lever 5l is allowed to rise until the operator ascertains that the bark hasbeen penetrated and that-the log andthe surface thusmade by the cutter-head have passed well under the gage-lever 50 which is now brought to bear upon the newlycut surface and the gage-lever 5I is released. By holding the gage-lever 50 at itsnormal position the cutter-head will continueft cut down to the surface thus established, or deeper if desired by allowing the gage-lever 50 to rise slightly.

' Asthe end of the log reaches the position of the unit A, the lmachineryfis'stopped anda wrap of the chain I l 'is thrown around the log in contactwith the. surfaceforrned by the cutterhead 22. The carriage `I1 is retractedby operation of the pneumatic cylinder 20 under control of the justable, yet cooperative.

valve 51' until the chain lvl is snugly in place. The motors are again set in operation and the bark-stripping process as described continued until the entire log has been cleaned of bark.

Now it will be observed that the cutter-head will, under guidance of the gage-levers, rise and fall to conform to the elevations of the successive portions of the log presented, and the depth to which the cutter-head penetrates is under constant and instant control so that irregularities in bark thickness and contour of the log surface may be followed with such exactness as may be desired.

vActual surfacing of the log may be controlled by means of the tilting screws 48 and 49 which allow rof adjusting the inclination of the cutter- Ahead axis to the exact relationship to the taper of the log required for smooth cutting.

In the embodiment shown, the chains Il and 59 are driven by electric motors with suitable controls thusallowing of a difference in the actual speed of travel of the two chains to compensate-for differences in diameter of the log at the respective places ofapplication of the chains. However, identical longitudinal urge ofthe log is provided by the two chains because the two sheaves I2A and 64 may be adjusted as to distance from. the respective cooperating sheaves I3 and 63 to exact identity or some different distances to provide such strain between the two feeding devices as will rmly control the longitudinal movement ofthe log.

The invention, therefore, resides in the special combination of elements adapted in relative adjustment to the log Vto which every member of the coasting combination is independently ad- Specically, the two chains may be adjusted to operative lengths suited to the particular portions of the log engaged and are by inherent nature conformable to the irregular shape of the log, yet will coactively rotate, feed, and control the log. though diierent lengths .of chain are required and different rates of travel thereof necessitated.

The cutter-head likewise adapts itself by means of the controls and adjustments described, to al1 manner of shapes, diameters, and irregularities cooperatively fed thereto by the chains.

- AllY ofthe adjustments are flexible while in operation and are. so provided for as to allow of simple operation so that the apparatus, itself, is peculiarly adapted to a specic method of barking the log which in itself is novel and rendered practicable by the apparatus described.

i Having described my invention, what I claim 1. Log barking apparatus comprising, a float, a vertically adjustable cutter-head mounted on said float, and a power driven chain mounted on said float and'extending therefrom to make helical contact with a log'to be barked to feed the surface of the latter into progressive engagement with said cutter-head in a helical path 1vvhile said log floats in the water alongside said 2. Log barking apparatus comprising, a float, power driven feed units disposed in spaced relationship on said float, chains driven by said feeding units and extending from said float for helicalrwrapping about a log while said 10g floats in the wateralongside said float, and vertically adjustable cutter-head means mounted on said float medially of said log feedingY units.

EDWARD v. PREN'I'LCE. 

